Yes, i have a DUCT coming off of the chiller, up and over the cabinet. No separate fan. The chiller has it's own. This keeps heat from building up behind the system. If i wasn't renting this house i would have vented it up through the ceiling into the attic.
A coast to coast overflow skims the entire surface area quickly. no dead spots. It also helps turn more water through the filtration. Kinda like a water fall across the whole back of the tank.
Thanks for the comment on the lighting. I will be making it adjustable in the near future so it can be lowered. Right now it sits 15" over the water. I would like to have the ability to get it closer. Though my corals and clams seem to be doing just fine under it as it is now.